@Article{KayanoFerrRami:1997:SuCiPa,
               author = "Kayano, Mary Toshie and Ferreira, Nelson Jesus and Ramirez, Maria 
                         Cleofe Valverde",
                title = "Summer circulation patterns related to the upper tropospheric 
                         vortices over the tropical South Atlantic",
              journal = "Meteorology and Atmospheric Physics",
                 year = "1997",
               volume = "64",
               number = "3-4",
                pages = "203--213",
             keywords = "estudo do tempo e do clima, atlantico sul tropical, rainfall 
                         anomalies, oscillation, atmosphere.",
             abstract = "Daily 200-hPa relative vorticity data have been used to study the 
                         dominant patterns related to the cyclonic vortices over the South 
                         Atlantic Ocean in the vicinities of northeast Brazil, during the 
                         1980-1989 period. Reference modes were obtained through empirical 
                         orthogonal function (EOF) analysis of the 200-hPa filtered 
                         vorticity anomalies over northeast Brazil, considering all the 
                         southern hemisphere (SH) summers within the study period. The 
                         amplitude time series of the first reference mode, separately for 
                         each SH summer, was correlated with the corresponding filtered 
                         vorticity anomalies in a larger area extending from 20 N to 40 S 
                         and between 120 W and 20 W. The correlation patterns feature a 
                         wave-like structure along eastern South America, with three main 
                         centers: the first one, over the South Atlantic off the northeast 
                         Brazil coast, is associated with the cyclonic vortices; the second 
                         one, over eastern Brazil, represents the corresponding anomalously 
                         amplified ridges; and the third one, over southern Brazil/Uruguay, 
                         is related to the equatorward incursions of midlatitude upper 
                         level troughs. This wave-like pattern is consistent with with the 
                         vortex formation mechanism suggested in previous works. Another 
                         wave-like pattern southwest-northeast oriented is evident over the 
                         tropical southeastern Pacific, for some years. The interannual 
                         variability of these patterns is discussed in this paper.",
                 issn = "0177-7971",
                label = "7905",
           targetfile = "10.1007_BF01029693.pdf",
        urlaccessdate = "03 maio 2024"
}